Helmet Therapy for Deformational Plagiocephaly: Clinical Outcomes and Considerations

<b>Background/Objectives</b>: Deformational plagiocephaly (DP) is defined as an asymmetrical flattening of infants' occipital skull. Helmet therapy is one of the treatments reported that can reduce skull deformity by guiding the growing direction of the head. However, its effectiveness remains insufficiently validated in the literature due to variability in treatment protocols and regimes. This study aims to evaluate the clinical outcomes of helmet therapy in infants with deformational plagiocephaly. <b>Methods</b>: This single-center retrospective study was conducted at a tertiary university hospital and included 30 consecutive infants (mean age 7.83 ± 2.51 months) who attended a pediatric orthopedic outpatient clinic between 2022 and 2025. Infants without craniosynostosis and with cranial vault asymmetry index (CVAI) ≥ 5% were prescribed a course of helmet therapy (mean duration 3.77 ± 2.37 months). The primary outcome was the change in CVAI. <b>Results</b>: The mean CVAI (%) significantly decreased from 7.57 ± 2.45 to 6.10 ± 2.63 (<i>p</i> = 0.002). The effect of helmet therapy was dose-dependent, with greater improvement observed in infants wearing the helmet for at least 6 h per day. Poor compliance and predominantly daytime helmet use were associated with less improvement. Increased sweating and mild skin redness were the most common reported adverse effects, but the skin redness can be relieved by proper donning of the helmet. <b>Conclusions</b>: Helmet therapy is effective for infants with plagiocephaly when initiated early and with high compliance of helmet use. Greater improvements were observed in infants using the helmet during sleeping. Further multi-center studies with a larger sample size and longer follow-up are recommended.